1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Marvell PXA27x family clocks
4  *
5  * Copyright (C) 2014 Robert Jarzmik
6  *
7  * Heavily inspired from former arch/arm/mach-pxa/clock.c.
8  */
9 #include <linux/clk-provider.h>
10 #include <linux/io.h>
11 #include <linux/clk.h>
12 #include <linux/clkdev.h>
13 #include <linux/of.h>
14 #include <linux/soc/pxa/smemc.h>
15 #include <linux/clk/pxa.h>
16 
17 #include <dt-bindings/clock/pxa-clock.h>
18 #include "clk-pxa.h"
19 #include "clk-pxa2xx.h"
20 
21 #define KHz 1000
22 #define MHz (1000 * 1000)
23 
24 enum {
25 	PXA_CORE_13Mhz = 0,
26 	PXA_CORE_RUN,
27 	PXA_CORE_TURBO,
28 };
29 
30 enum {
31 	PXA_BUS_13Mhz = 0,
32 	PXA_BUS_RUN,
33 };
34 
35 enum {
36 	PXA_LCD_13Mhz = 0,
37 	PXA_LCD_RUN,
38 };
39 
40 enum {
41 	PXA_MEM_13Mhz = 0,
42 	PXA_MEM_SYSTEM_BUS,
43 	PXA_MEM_RUN,
44 };
45 
46 #define PXA27x_CLKCFG(B, HT, T)			\
47 	(CLKCFG_FCS |				\
48 	 ((B)  ? CLKCFG_FASTBUS : 0) |		\
49 	 ((HT) ? CLKCFG_HALFTURBO : 0) |	\
50 	 ((T)  ? CLKCFG_TURBO : 0))
51 #define PXA27x_CCCR(A, L, N2) (A << 25 | N2 << 7 | L)
52 
53 /* Define the refresh period in mSec for the SDRAM and the number of rows */
54 #define SDRAM_TREF	64	/* standard 64ms SDRAM */
55 
56 static void __iomem *clk_regs;
57 
58 static const char * const get_freq_khz[] = {
59 	"core", "run", "cpll", "memory",
60 	"system_bus"
61 };
62 
mdrefr_dri(unsigned int freq_khz)63 static u32 mdrefr_dri(unsigned int freq_khz)
64 {
65 	u32 interval = freq_khz * SDRAM_TREF / pxa2xx_smemc_get_sdram_rows();
66 
67 	return (interval - 31) / 32;
68 }
69 
70 /*
71  * Get the clock frequency as reflected by CCSR and the turbo flag.
72  * We assume these values have been applied via a fcs.
73  * If info is not 0 we also display the current settings.
74  */
pxa27x_get_clk_frequency_khz(int info)75 unsigned int pxa27x_get_clk_frequency_khz(int info)
76 {
77 	struct clk *clk;
78 	unsigned long clks[5];
79 	int i;
80 
81 	for (i = 0; i < 5; i++) {
82 		clk = clk_get(NULL, get_freq_khz[i]);
83 		if (IS_ERR(clk)) {
84 			clks[i] = 0;
85 		} else {
86 			clks[i] = clk_get_rate(clk);
87 			clk_put(clk);
88 		}
89 	}
90 	if (info) {
91 		pr_info("Run Mode clock: %ld.%02ldMHz\n",
92 			clks[1] / 1000000, (clks[1] % 1000000) / 10000);
93 		pr_info("Turbo Mode clock: %ld.%02ldMHz\n",
94 			clks[2] / 1000000, (clks[2] % 1000000) / 10000);
95 		pr_info("Memory clock: %ld.%02ldMHz\n",
96 			clks[3] / 1000000, (clks[3] % 1000000) / 10000);
97 		pr_info("System bus clock: %ld.%02ldMHz\n",
98 			clks[4] / 1000000, (clks[4] % 1000000) / 10000);
99 	}
100 	return (unsigned int)clks[0] / KHz;
101 }
102 
pxa27x_is_ppll_disabled(void)103 static bool pxa27x_is_ppll_disabled(void)
104 {
105 	unsigned long ccsr = readl(clk_regs + CCSR);
106 
107 	return ccsr & (1 << CCCR_PPDIS_BIT);
108 }
109 
110 #define PXA27X_CKEN(dev_id, con_id, parents, mult_hp, div_hp,		\
111 		    bit, is_lp, flags)					\
112 	PXA_CKEN(dev_id, con_id, bit, parents, 1, 1, mult_hp, div_hp,	\
113 		 is_lp,  CKEN, CKEN_ ## bit, flags)
114 #define PXA27X_PBUS_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)	\
115 	PXA27X_CKEN(dev_id, con_id, pxa27x_pbus_parents, mult_hp,	\
116 		    div_hp, bit, pxa27x_is_ppll_disabled, 0)
117 
118 PARENTS(pxa27x_pbus) = { "osc_13mhz", "ppll_312mhz" };
119 PARENTS(pxa27x_sbus) = { "system_bus", "system_bus" };
120 PARENTS(pxa27x_32Mhz_bus) = { "osc_32_768khz", "osc_32_768khz" };
121 PARENTS(pxa27x_lcd_bus) = { "lcd_base", "lcd_base" };
122 PARENTS(pxa27x_membus) = { "lcd_base", "lcd_base" };
123 
124 #define PXA27X_CKEN_1RATE(dev_id, con_id, bit, parents, delay)		\
125 	PXA_CKEN_1RATE(dev_id, con_id, bit, parents,			\
126 		       CKEN, CKEN_ ## bit, 0)
127 #define PXA27X_CKEN_1RATE_AO(dev_id, con_id, bit, parents, delay)	\
128 	PXA_CKEN_1RATE(dev_id, con_id, bit, parents,			\
129 		       CKEN, CKEN_ ## bit, CLK_IGNORE_UNUSED)
130 
131 static struct desc_clk_cken pxa27x_clocks[] __initdata = {
132 	PXA27X_PBUS_CKEN("pxa2xx-uart.0", NULL, FFUART, 2, 42, 1),
133 	PXA27X_PBUS_CKEN("pxa2xx-uart.1", NULL, BTUART, 2, 42, 1),
134 	PXA27X_PBUS_CKEN("pxa2xx-uart.2", NULL, STUART, 2, 42, 1),
135 	PXA27X_PBUS_CKEN("pxa2xx-i2s", NULL, I2S, 2, 51, 0),
136 	PXA27X_PBUS_CKEN("pxa2xx-i2c.0", NULL, I2C, 2, 19, 0),
137 	PXA27X_PBUS_CKEN("pxa27x-udc", NULL, USB, 2, 13, 5),
138 	PXA27X_PBUS_CKEN("pxa2xx-mci.0", NULL, MMC, 2, 32, 0),
139 	PXA27X_PBUS_CKEN("pxa2xx-ir", "FICPCLK", FICP, 2, 13, 0),
140 	PXA27X_PBUS_CKEN("pxa27x-ohci", NULL, USBHOST, 2, 13, 0),
141 	PXA27X_PBUS_CKEN("pxa2xx-i2c.1", NULL, PWRI2C, 1, 24, 0),
142 	PXA27X_PBUS_CKEN("pxa27x-ssp.0", NULL, SSP1, 1, 24, 0),
143 	PXA27X_PBUS_CKEN("pxa27x-ssp.1", NULL, SSP2, 1, 24, 0),
144 	PXA27X_PBUS_CKEN("pxa27x-ssp.2", NULL, SSP3, 1, 24, 0),
145 	PXA27X_PBUS_CKEN("pxa27x-pwm.0", NULL, PWM0, 1, 24, 0),
146 	PXA27X_PBUS_CKEN("pxa27x-pwm.1", NULL, PWM1, 1, 24, 0),
147 	PXA27X_PBUS_CKEN(NULL, "MSLCLK", MSL, 2, 13, 0),
148 	PXA27X_PBUS_CKEN(NULL, "USIMCLK", USIM, 2, 13, 0),
149 	PXA27X_PBUS_CKEN(NULL, "MSTKCLK", MEMSTK, 2, 32, 0),
150 	PXA27X_PBUS_CKEN(NULL, "AC97CLK", AC97, 1, 1, 0),
151 	PXA27X_PBUS_CKEN(NULL, "AC97CONFCLK", AC97CONF, 1, 1, 0),
152 	PXA27X_PBUS_CKEN(NULL, "OSTIMER0", OSTIMER, 1, 96, 0),
153 
154 	PXA27X_CKEN_1RATE("pxa27x-keypad", NULL, KEYPAD,
155 			  pxa27x_32Mhz_bus_parents, 0),
156 	PXA27X_CKEN_1RATE(NULL, "IMCLK", IM, pxa27x_sbus_parents, 0),
157 	PXA27X_CKEN_1RATE("pxa2xx-fb", NULL, LCD, pxa27x_lcd_bus_parents, 0),
158 	PXA27X_CKEN_1RATE("pxa27x-camera.0", NULL, CAMERA,
159 			  pxa27x_lcd_bus_parents, 0),
160 	PXA27X_CKEN_1RATE_AO("pxa2xx-pcmcia", NULL, MEMC,
161 			     pxa27x_membus_parents, 0),
162 
163 };
164 
165 /*
166  * PXA270 definitions
167  *
168  * For the PXA27x:
169  * Control variables are A, L, 2N for CCCR; B, HT, T for CLKCFG.
170  *
171  * A = 0 => memory controller clock from table 3-7,
172  * A = 1 => memory controller clock = system bus clock
173  * Run mode frequency	= 13 MHz * L
174  * Turbo mode frequency = 13 MHz * L * N
175  * System bus frequency = 13 MHz * L / (B + 1)
176  *
177  * In CCCR:
178  * A = 1
179  * L = 16	  oscillator to run mode ratio
180  * 2N = 6	  2 * (turbo mode to run mode ratio)
181  *
182  * In CCLKCFG:
183  * B = 1	  Fast bus mode
184  * HT = 0	  Half-Turbo mode
185  * T = 1	  Turbo mode
186  *
187  * For now, just support some of the combinations in table 3-7 of
188  * PXA27x Processor Family Developer's Manual to simplify frequency
189  * change sequences.
190  */
191 static struct pxa2xx_freq pxa27x_freqs[] = {
192 	{104000000, 104000, PXA27x_CCCR(1,  8, 2), 0, PXA27x_CLKCFG(1, 0, 1) },
193 	{156000000, 104000, PXA27x_CCCR(1,  8, 3), 0, PXA27x_CLKCFG(1, 0, 1) },
194 	{208000000, 208000, PXA27x_CCCR(0, 16, 2), 1, PXA27x_CLKCFG(0, 0, 1) },
195 	{312000000, 208000, PXA27x_CCCR(1, 16, 3), 1, PXA27x_CLKCFG(1, 0, 1) },
196 	{416000000, 208000, PXA27x_CCCR(1, 16, 4), 1, PXA27x_CLKCFG(1, 0, 1) },
197 	{520000000, 208000, PXA27x_CCCR(1, 16, 5), 1, PXA27x_CLKCFG(1, 0, 1) },
198 	{624000000, 208000, PXA27x_CCCR(1, 16, 6), 1, PXA27x_CLKCFG(1, 0, 1) },
199 };
200 
clk_pxa27x_cpll_get_rate(struct clk_hw * hw,unsigned long parent_rate)201 static unsigned long clk_pxa27x_cpll_get_rate(struct clk_hw *hw,
202 	unsigned long parent_rate)
203 {
204 	unsigned long clkcfg;
205 	unsigned int t, ht;
206 	unsigned int l, L, n2, N;
207 	unsigned long ccsr = readl(clk_regs + CCSR);
208 
209 	asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
210 	t  = clkcfg & (1 << 0);
211 	ht = clkcfg & (1 << 2);
212 
213 	l  = ccsr & CCSR_L_MASK;
214 	n2 = (ccsr & CCSR_N2_MASK) >> CCSR_N2_SHIFT;
215 	L  = l * parent_rate;
216 	N  = (L * n2) / 2;
217 
218 	return N;
219 }
220 
clk_pxa27x_cpll_determine_rate(struct clk_hw * hw,struct clk_rate_request * req)221 static int clk_pxa27x_cpll_determine_rate(struct clk_hw *hw,
222 					  struct clk_rate_request *req)
223 {
224 	return pxa2xx_determine_rate(req, pxa27x_freqs,
225 				     ARRAY_SIZE(pxa27x_freqs));
226 }
227 
clk_pxa27x_cpll_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)228 static int clk_pxa27x_cpll_set_rate(struct clk_hw *hw, unsigned long rate,
229 				    unsigned long parent_rate)
230 {
231 	int i;
232 
233 	pr_debug("%s(rate=%lu parent_rate=%lu)\n", __func__, rate, parent_rate);
234 	for (i = 0; i < ARRAY_SIZE(pxa27x_freqs); i++)
235 		if (pxa27x_freqs[i].cpll == rate)
236 			break;
237 
238 	if (i >= ARRAY_SIZE(pxa27x_freqs))
239 		return -EINVAL;
240 
241 	pxa2xx_cpll_change(&pxa27x_freqs[i], mdrefr_dri, clk_regs + CCCR);
242 	return 0;
243 }
244 
245 PARENTS(clk_pxa27x_cpll) = { "osc_13mhz" };
246 RATE_OPS(clk_pxa27x_cpll, "cpll");
247 
clk_pxa27x_lcd_base_get_rate(struct clk_hw * hw,unsigned long parent_rate)248 static unsigned long clk_pxa27x_lcd_base_get_rate(struct clk_hw *hw,
249 						  unsigned long parent_rate)
250 {
251 	unsigned int l, osc_forced;
252 	unsigned long ccsr = readl(clk_regs + CCSR);
253 	unsigned long cccr = readl(clk_regs + CCCR);
254 
255 	l  = ccsr & CCSR_L_MASK;
256 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
257 	if (osc_forced) {
258 		if (cccr & (1 << CCCR_LCD_26_BIT))
259 			return parent_rate * 2;
260 		else
261 			return parent_rate;
262 	}
263 
264 	if (l <= 7)
265 		return parent_rate;
266 	if (l <= 16)
267 		return parent_rate / 2;
268 	return parent_rate / 4;
269 }
270 
clk_pxa27x_lcd_base_get_parent(struct clk_hw * hw)271 static u8 clk_pxa27x_lcd_base_get_parent(struct clk_hw *hw)
272 {
273 	unsigned int osc_forced;
274 	unsigned long ccsr = readl(clk_regs + CCSR);
275 
276 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
277 	if (osc_forced)
278 		return PXA_LCD_13Mhz;
279 	else
280 		return PXA_LCD_RUN;
281 }
282 
283 PARENTS(clk_pxa27x_lcd_base) = { "osc_13mhz", "run" };
284 MUX_RO_RATE_RO_OPS(clk_pxa27x_lcd_base, "lcd_base");
285 
pxa27x_register_plls(void)286 static void __init pxa27x_register_plls(void)
287 {
288 	clk_register_fixed_rate(NULL, "osc_13mhz", NULL,
289 				CLK_GET_RATE_NOCACHE,
290 				13 * MHz);
291 	clkdev_pxa_register(CLK_OSC32k768, "osc_32_768khz", NULL,
292 			    clk_register_fixed_rate(NULL, "osc_32_768khz", NULL,
293 						    CLK_GET_RATE_NOCACHE,
294 						    32768 * KHz));
295 	clk_register_fixed_rate(NULL, "clk_dummy", NULL, 0, 0);
296 	clk_register_fixed_factor(NULL, "ppll_312mhz", "osc_13mhz", 0, 24, 1);
297 }
298 
clk_pxa27x_core_get_parent(struct clk_hw * hw)299 static u8 clk_pxa27x_core_get_parent(struct clk_hw *hw)
300 {
301 	unsigned long clkcfg;
302 	unsigned int t, ht, osc_forced;
303 	unsigned long ccsr = readl(clk_regs + CCSR);
304 
305 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
306 	if (osc_forced)
307 		return PXA_CORE_13Mhz;
308 
309 	asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
310 	t  = clkcfg & (1 << 0);
311 	ht = clkcfg & (1 << 2);
312 
313 	if (ht || t)
314 		return PXA_CORE_TURBO;
315 	return PXA_CORE_RUN;
316 }
317 
clk_pxa27x_core_set_parent(struct clk_hw * hw,u8 index)318 static int clk_pxa27x_core_set_parent(struct clk_hw *hw, u8 index)
319 {
320 	if (index > PXA_CORE_TURBO)
321 		return -EINVAL;
322 
323 	pxa2xx_core_turbo_switch(index == PXA_CORE_TURBO);
324 
325 	return 0;
326 }
327 
clk_pxa27x_core_determine_rate(struct clk_hw * hw,struct clk_rate_request * req)328 static int clk_pxa27x_core_determine_rate(struct clk_hw *hw,
329 					  struct clk_rate_request *req)
330 {
331 	return __clk_mux_determine_rate(hw, req);
332 }
333 
334 PARENTS(clk_pxa27x_core) = { "osc_13mhz", "run", "cpll" };
335 MUX_OPS(clk_pxa27x_core, "core", CLK_SET_RATE_PARENT);
336 
clk_pxa27x_run_get_rate(struct clk_hw * hw,unsigned long parent_rate)337 static unsigned long clk_pxa27x_run_get_rate(struct clk_hw *hw,
338 					     unsigned long parent_rate)
339 {
340 	unsigned long ccsr = readl(clk_regs + CCSR);
341 	unsigned int n2 = (ccsr & CCSR_N2_MASK) >> CCSR_N2_SHIFT;
342 
343 	return (parent_rate / n2) * 2;
344 }
345 PARENTS(clk_pxa27x_run) = { "cpll" };
346 RATE_RO_OPS(clk_pxa27x_run, "run");
347 
pxa27x_register_core(void)348 static void __init pxa27x_register_core(void)
349 {
350 	clkdev_pxa_register(CLK_NONE, "cpll", NULL,
351 			    clk_register_clk_pxa27x_cpll());
352 	clkdev_pxa_register(CLK_NONE, "run", NULL,
353 			    clk_register_clk_pxa27x_run());
354 	clkdev_pxa_register(CLK_CORE, "core", NULL,
355 			    clk_register_clk_pxa27x_core());
356 }
357 
clk_pxa27x_system_bus_get_rate(struct clk_hw * hw,unsigned long parent_rate)358 static unsigned long clk_pxa27x_system_bus_get_rate(struct clk_hw *hw,
359 						    unsigned long parent_rate)
360 {
361 	unsigned long clkcfg;
362 	unsigned int b, osc_forced;
363 	unsigned long ccsr = readl(clk_regs + CCSR);
364 
365 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
366 	asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
367 	b  = clkcfg & (1 << 3);
368 
369 	if (osc_forced)
370 		return parent_rate;
371 	if (b)
372 		return parent_rate;
373 	else
374 		return parent_rate / 2;
375 }
376 
clk_pxa27x_system_bus_get_parent(struct clk_hw * hw)377 static u8 clk_pxa27x_system_bus_get_parent(struct clk_hw *hw)
378 {
379 	unsigned int osc_forced;
380 	unsigned long ccsr = readl(clk_regs + CCSR);
381 
382 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
383 	if (osc_forced)
384 		return PXA_BUS_13Mhz;
385 	else
386 		return PXA_BUS_RUN;
387 }
388 
389 PARENTS(clk_pxa27x_system_bus) = { "osc_13mhz", "run" };
390 MUX_RO_RATE_RO_OPS(clk_pxa27x_system_bus, "system_bus");
391 
clk_pxa27x_memory_get_rate(struct clk_hw * hw,unsigned long parent_rate)392 static unsigned long clk_pxa27x_memory_get_rate(struct clk_hw *hw,
393 						unsigned long parent_rate)
394 {
395 	unsigned int a, l, osc_forced;
396 	unsigned long cccr = readl(clk_regs + CCCR);
397 	unsigned long ccsr = readl(clk_regs + CCSR);
398 
399 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
400 	a = cccr & (1 << CCCR_A_BIT);
401 	l  = ccsr & CCSR_L_MASK;
402 
403 	if (osc_forced || a)
404 		return parent_rate;
405 	if (l <= 10)
406 		return parent_rate;
407 	if (l <= 20)
408 		return parent_rate / 2;
409 	return parent_rate / 4;
410 }
411 
clk_pxa27x_memory_get_parent(struct clk_hw * hw)412 static u8 clk_pxa27x_memory_get_parent(struct clk_hw *hw)
413 {
414 	unsigned int osc_forced, a;
415 	unsigned long cccr = readl(clk_regs + CCCR);
416 	unsigned long ccsr = readl(clk_regs + CCSR);
417 
418 	osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
419 	a = cccr & (1 << CCCR_A_BIT);
420 	if (osc_forced)
421 		return PXA_MEM_13Mhz;
422 	if (a)
423 		return PXA_MEM_SYSTEM_BUS;
424 	else
425 		return PXA_MEM_RUN;
426 }
427 
428 PARENTS(clk_pxa27x_memory) = { "osc_13mhz", "system_bus", "run" };
429 MUX_RO_RATE_RO_OPS(clk_pxa27x_memory, "memory");
430 
431 #define DUMMY_CLK(_con_id, _dev_id, _parent) \
432 	{ .con_id = _con_id, .dev_id = _dev_id, .parent = _parent }
433 struct dummy_clk {
434 	const char *con_id;
435 	const char *dev_id;
436 	const char *parent;
437 };
438 static struct dummy_clk dummy_clks[] __initdata = {
439 	DUMMY_CLK(NULL, "pxa27x-gpio", "osc_32_768khz"),
440 	DUMMY_CLK(NULL, "pxa-rtc", "osc_32_768khz"),
441 	DUMMY_CLK(NULL, "sa1100-rtc", "osc_32_768khz"),
442 	DUMMY_CLK("UARTCLK", "pxa2xx-ir", "STUART"),
443 };
444 
pxa27x_dummy_clocks_init(void)445 static void __init pxa27x_dummy_clocks_init(void)
446 {
447 	struct clk *clk;
448 	struct dummy_clk *d;
449 	const char *name;
450 	int i;
451 
452 	for (i = 0; i < ARRAY_SIZE(dummy_clks); i++) {
453 		d = &dummy_clks[i];
454 		name = d->dev_id ? d->dev_id : d->con_id;
455 		clk = clk_register_fixed_factor(NULL, name, d->parent, 0, 1, 1);
456 		clk_register_clkdev(clk, d->con_id, d->dev_id);
457 	}
458 }
459 
pxa27x_base_clocks_init(void)460 static void __init pxa27x_base_clocks_init(void)
461 {
462 	pxa27x_register_plls();
463 	pxa27x_register_core();
464 	clkdev_pxa_register(CLK_NONE, "system_bus", NULL,
465 			    clk_register_clk_pxa27x_system_bus());
466 	clkdev_pxa_register(CLK_NONE, "memory", NULL,
467 			    clk_register_clk_pxa27x_memory());
468 	clk_register_clk_pxa27x_lcd_base();
469 }
470 
pxa27x_clocks_init(void __iomem * regs)471 int __init pxa27x_clocks_init(void __iomem *regs)
472 {
473 	clk_regs = regs;
474 	pxa27x_base_clocks_init();
475 	pxa27x_dummy_clocks_init();
476 	return clk_pxa_cken_init(pxa27x_clocks, ARRAY_SIZE(pxa27x_clocks), regs);
477 }
478 
pxa27x_dt_clocks_init(struct device_node * np)479 static void __init pxa27x_dt_clocks_init(struct device_node *np)
480 {
481 	pxa27x_clocks_init(ioremap(0x41300000ul, 0x10));
482 	clk_pxa_dt_common_init(np);
483 }
484 CLK_OF_DECLARE(pxa_clks, "marvell,pxa270-clocks", pxa27x_dt_clocks_init);
485